Client was notified CCITCPGW took a dump:
9S02 18099 01:14:46.88 IEA794I SVC DUMP HAS CAPTURED: 590 DUMPID=006 REQUESTED BY JOB (CCITCPGW) DUMP TITLE=COMPON=BPX,COMPID=SCPX1,ISSUER=BPXMIPCE,MODULE=BPXLU KW +19B4,ABEND=S0EC6,REASON=0836048F
IBM code problem.
Client advised that CCITCPGW encountered abend but appears to have recovered and reestablished connections.
IBM has accepted this as a software defect and opened APAR OA53761 to address it.
As of 5/9/2018 the correcting fix from IBM is available.